Authors' response.

Sir,

The authors appreciate the comments of the esteemed reader of our article1. The authors agree with the observation that the occurrence of vitamin-D deficiency/insufficiency of 73.5 per cent (115/157) among individuals with prediabetes in our study was reflective of the widespread vitamin-D deficiency in the general population. The same has already been mentioned in the summary of the article in the last paragraph of the discussion section. The primary objective of this cross-sectional study was not to evaluate the burden of vitamin-D deficiency/insufficiency in prediabetes, but to highlight the inverse correlation between vitamin-D and insulin resistance, even after adjusting for body mass index and glycated haemoglobin. In a subsequent prospective study, we have observed vitamin-D to be predictive of prediabetes reversal to normoglycaemia2. Further, in the first open labelled randomized controlled trial from India, we observed vitamin-D supplementation to be beneficial in improving glycaemic outcomes in prediabetes and it was associated with improvement in insulin resistance, inflammatory cytokines and lipids3.